1. Technical Field
The present invention relates generally to semiconductor device fabrication, and more particularly, to methods of depositing a high dielectric constant (Hi-K) dielectric layer with increased throughput while maintaining low leakage and high reliability, and the layer formed.
2. Related Art
High dielectric constant (Hi-K) materials are currently being implemented in advanced semiconductor device fabrication. For example, the Hi-K materials are replacing dielectric materials such as silicon dioxide (SiO2) and silicon nitride (Si3N4) used in passive devices (especially metal-insulator-metal capacitors). Such Hi-K materials increase the capacitance density with a thicker dielectric film by virtue of their higher dielectric constant. Overall, a Hi-K material that satisfies the industry reliability standard of 100,000 power-on-hours (POH) is desirable. For radio frequency (RF) applications, linearity (VCC), dielectric loss, and dielectric relaxation are also of importance. As the dielectric constant of materials increases, most of the above-described electrical parameters begin to degrade.
A challenge for Hi-K dielectric materials is obtaining high throughput of wafers during fabrication, while maintaining reliability. In particular, current deposition techniques such as atomic layer deposition (ALD) are extremely slow due to monolayer growth. Conventionally, there are two oxidants, which are used extensively, that can be used to deposit Hi-K dielectric materials: oxygen (O2) and ozone (O3). Ozone has a growth rate that could be, for example, 60% greater than oxygen, and thus allows a higher throughput. Unfortunately, ozone-based films results in a lower reliability than oxygen-based films, and thus cannot always be used.
In view of the foregoing, there is a need in the art for a method of depositing a Hi-K dielectric material that has increased throughput without loss of reliability.